Wrong water temperature on lakes
The water temp. on big lakes seems to be much less
compared to readings from satellite measurments.
For example windy shows 8C at Prespa lake (Greek-Albanian border)
while NASA measures it 19C.
The same for Lake Balaton, Hungary, Lake Geneva etc.
.... the water temp. for that lake (as provided by ECMWF) is 18C, and is normal.
I don't know where is coming from the temp. provided in windy (8C)
maybe it is an interpolation issue,
like the one mentioned here (currents)